In contemporary Western Europe, both scholars and the public discuss the consequences of a rising share of a comparatively religious Muslim population for societal coexistence. Yet we know surprisingly little about how religion and religiosity shape social relationships. Focusing on adolescents’ friendship networks, we examine how religion and religiosity affect intra- and inter-group friendship choices. While youth should generally prefer to befriend peers of the same religion, this religious homophily should be more pronounced for highly than for less religious youth. Against the background of rising anti-Muslim attitudes in Europe, Christian and non-religious youth further may be particularly hesitant to befriend Muslim peers, and especially highly religious ones. We analysed three waves of German longitudinal friendship network data from ethnically diverse schools. Regarding intra-group friendships, while Muslim youth indeed preferred to befriend Muslim peers, Christian youth displayed no evidence of religious homophily. For Muslims, higher levels of religiosity further increased this preference. Regarding inter-group friendships, irrespective of their individual religiosity, Muslim youth were socially divided from their non-Muslim peers, as both Christian and nonreligious youth were reluctant to befriend Muslim peers. In sum, in the German context, religion itself rather than religiosity seems to matter most for adolescents’ friendship choices.
